/*
 * Copyright (c) 2010, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0, which is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package org.glassfish.grizzly.samples.simpleauth;

import java.io.IOException;
import java.nio.charset.Charset;
import java.util.LinkedList;
import java.util.List;
import java.util.logging.Logger;

import org.glassfish.grizzly.filterchain.FilterChainBuilder;
import org.glassfish.grizzly.filterchain.TransportFilter;
import org.glassfish.grizzly.nio.transport.TCPNIOTransport;
import org.glassfish.grizzly.nio.transport.TCPNIOTransportBuilder;
import org.glassfish.grizzly.samples.echo.EchoFilter;

/**
 * Server implementation, which echoes message, only if client was authenticated :) Client and server exchange String
 * based messages:
 *
 * (1) MultiLinePacket = command *(parameter LF) LF parameter = TEXT (ASCII)
 *
 * Server filters are built in a following way:
 *
 * {@link TransportFilter} - reads/writes data from/to network {@link MultiStringFilter} - translates Buffer <->
 * List&lt;String&gt; {@link MultiLineFilter} - translates String <-> MultiLinePacket (see 1) {@link ServerAuthFilter} -
 * checks authentication header in an incoming packets. {@link org.glassfish.grizzly.samples.echo.EchoFilter} - sends
 * echo to a client.
 *
 * @author Alexey Stashok
 */
public class Server {
    private static final Logger logger = Logger.getLogger(Server.class.getName());

    public static final String HOST = "localhost";
    public static final int PORT = 7777;

    public static void main(String[] args) throws IOException {
        // Create a FilterChain using FilterChainBuilder
        FilterChainBuilder filterChainBuilder = FilterChainBuilder.stateless();
        // Add TransportFilter, which is responsible
        // for reading and writing data to the connection
        filterChainBuilder.add(new TransportFilter());
        // MultiStringFilter is responsible for parsing list of string lines
        filterChainBuilder.add(new MultiStringFilter(Charset.forName("ASCII"), "\n") {

            @Override
            protected List<String> createInList() {
                // overwrite createInList to return LinkedList instead of ArrayList
                return new LinkedList<>();
            }
        });
        // MultiLineFilter is responsible for gathering parsed lines in a single multi line packet
        filterChainBuilder.add(new MultiLineFilter(""));
        // AuthFilter is responsible for a client authentication
        filterChainBuilder.add(new ServerAuthFilter());
        // EchoServer sends the client message back
        filterChainBuilder.add(new EchoFilter());

        // Create TCP transport
        final TCPNIOTransport transport = TCPNIOTransportBuilder.newInstance().build();
        transport.setProcessor(filterChainBuilder.build());

        try {
            // binding transport to start listen on certain host and port
            transport.bind(HOST, PORT);

            // start the transport
            transport.start();

            logger.info("Press any key to stop the server...");
            System.in.read();
        } finally {
            logger.info("Stopping transport...");
            // stop the transport
            transport.shutdownNow();

            logger.info("Stopped transport...");
        }
    }
}
